K-5 Math Teaching Resources
Triangle Pack
With so many different types of triangles, it can be a challenge for young mathematicians to keep them all straight. Luckily this set of printable triangles is here to engage children in comparing and sorting triangles by their...
Curated OER
Geometric Figures-Triangles
Fourth graders explore triangles. In this math lesson, 4th graders discuss the different types of triangles. Students create triangles using wiki sticks. Students complete an online matching game.
McGraw Hill
Triangles
After reviewing characteristics of seven types of triangles, young geometers discover how to find the missing angle of a triangle. Then, they practice identifying triangles, find missing angles, and find missing side lengths of...
Curated OER
Geometric Properties
Learners find triangular angles using the angle theorem. For this geometry lesson, students describe labeled triangles, use the pythagorean theorem, and rewrite information about triangles in standard form.
Scholastic
Study Jams! Classify Triangles
Jam on with this multi-faceted activity teaching triangle classification. Start with a learner-paced lesson describing the different qualities of triangles and follow with a fun karaoke session. Also provided are two types...
Curated OER
Isosceles Triangles
Learners investigate triangles. In this shapes geometry lesson, students define and state the attributes for equilateral, scalene, and isosceles triangles. Learners locate the prefix "tri" in a variety of words and make connections with...
National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy...
Curated OER
Identifying Triangles
Sixth graders identify and define a variety of triangles. For this identification of triangles lesson, 6th graders draw examples of each triangle on a whiteboard, then complete a worksheet.
Curated OER
Acute Triangles
Learners study acute triangles. They measure angles using a protractor, then classify the triangles as either right, obtuse, or acute. Everyone creates a design for a Navajo rug using only acute triangles.
Curated OER
Triangles
Students draw triangles. In this shapes lesson, students discuss what they already know about triangles, what they are and what they are made up of. Students discuss the types of triangles and practice drawing each type.
Curated OER
Triangles
Students identify triangles in the real world and construct their own triangle using drinking straws. They explore abstract triangles and find additional geometric shapes such as trapezoids. Students discuss similar shapes and examine...
Raytheon
Understanding Triangles
In this understanding triangles activity, students read 6 pages of examples and explanations about identifying triangles, determining length of sides and degrees of angles, including the hypotenuse, then answer 28 questions, answers...
Curated OER
Triangles
Fourth graders participate in three experiments to gain understanding of triangles. For this triangles lesson, 4th graders use pipe cleaners to create bubble pipes, basketball hoops and bingo cards to display the characteristics of...
Curated OER
Angles, Triangles, Quadrilaterals, Circles and Related
Students classify angles. For this angles lesson, students explore the characteristics of angles, triangles, quadrilaterals and circles. They identify polygons and sing a classifying angles song. Students participate in a manipulative...
Curated OER
Exploring Centers of a Triangle: Part 2
Students model and solve a real-world problem by constructing the centroid of a triangle. They explore relationships of the medians of a triangle and investigate how the centroid partitions each of the medians. Students investigate...
Curated OER
Right Triangles
Learners classify triangles and make connections regarding angle measurements and attributes of acute, right, and obtuse triangles. They listen to teacher define and explain triangles. Everyone imagines a place where a broken wing for a...
Curated OER
Triangle Inequality Theorem
Young scholars use the inequality theorem to solve triangles and their properties. In this geometry instructional activity, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary...
Curated OER
Review of Triangles
Students investigate the Pythagorean Theorem. For this geometry lesson, students define angles and sides of right triangles. They calculate the area and surface area using formulas derived by the Pythagorean Theorem.
Curated OER
Scalene Triangles
Fifth graders identify and classify scalene, equilateral, and isosceles triangles. In this triangle instructional activity, 5th graders define the different attributes of 3 types of triangles and sort them by descriptions and...
Curated OER
Triangle Classification
Students classify different types of triangles. In this geometry lesson plan, students identify and use properties of triangles. They differentiate between isosceles and equilateral triangles.
Curated OER
Shape Up
Middle schoolers explore differents types of triangles and quadriaterals. In this polygon lesson, students model identify and compare two and three dimensional geometric figures. Middle schoolers create tangrams and discover the...
Curated OER
Angle-Side Relationships
Students calculate the different sides and angles of a triangle. In this geometry lesson, students use triangular properties to define the relationship between two triangle. They identify missing angles using the interior angle theorem.
Virginia Department of Education
Classifying Angles
Don't be obtuse, this geometry unit is the just the right resource for educating the acute young minds in your class. From classifying and measuring angles, to determining the congruence of shapes, this...
iMagine Machine
The Land of Venn - Geometric Defense
Young mathematicians use their geometry skills to save the Land of Venn in an engaging math game. A fun way to reinforce children's understanding of basic geometric figures and shapes.